1. European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe, Germany
2. CEA, DEN, Cadarache DEC/SESC, F-13108 St-Paul-Lez-Durance Cedex, France
3. Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, D-01314 Dresden, Germany